JP2016217353A - System for arranging emission reducing catalyst in exhaust duct of gas turbine engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas turbine power plant comprising an exhaust system including a transition duct, a flue gas exhaust duct, an exhaust stack outlet, and a catalyst.SOLUTION: An exhaust section for a gas turbine power plant includes: an exhaust duct in fluid communication with exhaust gas from a gas turbine engine, the exhaust gas flowing through the exhaust duct along a flow direction; and a catalyst supporting platform spanning a flow passage in the exhaust duct such that the exhaust gas passes through the platform, where the platform includes apertures having catalyst coated surfaces and the catalyst supporting platform has a front face which is not perpendicular to the flow direction.SELECTED DRAWING: Figure 1a

Description

  The present invention relates to a gas turbine power plant comprising an exhaust system including a transition duct, a flue gas exhaust duct, an exhaust stack outlet, and a catalyst, wherein the catalyst is arranged such that the exhaust stream contacts the catalyst at the exhaust duct. Has been.

The catalyst is inserted into the exhaust duct to remove contaminants from the exhaust gas of the gas turbine engine. These catalyst walls extend to the exhaust duct and are perpendicular to the exhaust gas flow through the duct. The wall rapidly increases in gas velocity as the exhaust gas flows through the wall openings, channels, or honeycomb holes. Rapid acceleration is accompanied by a large water (H ₂ O) pressure loss of up to 15 inches.
Large pressure losses are undesirable. In order to minimize the pressure drop, the flow path of the exhaust duct is provided with a large cross-sectional area in the direction of flow through the duct. Increasing the cross section of the exhaust duct increases the cost and mounting area of the duct.

US Patent Application No. 7,976,800

  A new orientation of the catalyst support platform is envisaged where the surface of the platform is inclined to the exhaust duct. Angling a catalyst support platform, eg, a wall, increases the exposed surface area of the platform and thus allows an increase in the number of openings through which exhaust gases flow. The greater the number of openings, the less pressure drop due to the catalyst support platform.

  The exhaust section of a gas turbine power plant is an exhaust duct that is in fluid communication with exhaust gas from a gas turbine engine, the exhaust gas flowing through the exhaust duct along a flow direction, and the exhaust gas passing through the platform. A catalyst support platform that extends to the exhaust duct flow path to pass therethrough, the platform including an opening having a catalyst coated surface, the catalyst support platform being disposed at an angle greater than 10 degrees relative to the flow direction. And a catalyst support platform including a portion.

  The catalyst support platform may have a substantially conical shape with a conical axis parallel to the flow direction, and the conical shape has a V-shaped cross section that converges in the flow direction. The opening may have an axis oriented in the range of 10 to 90 degrees with respect to the flow direction. The cone axis may also not be parallel to the flow direction.

  Further, the catalyst support platform can be oriented in a plane at an angle to the flow direction in the range of 10 to 90 degrees. Alternatively, the catalyst support platform can include steps that each include a riser in a plane substantially perpendicular to the flow direction and a tread in a plane substantially parallel to the flow direction.

  The exhaust section of the gas turbine power plant includes a transition duct, an exhaust duct, an exhaust outlet tube, and a porous catalyst support platform in the exhaust duct or exhaust outlet tube, the catalyst support platform receiving exhaust from the gas turbine engine. Extending across the exhaust flow path to flow through the platform, the catalyst support platform is positioned so that the exhaust flow contacts the catalyst at an angle to the direction of the exhaust flow in the range of 10-90 degrees.

1 is a diagram of an exemplary conventional exhaust system. FIG. FIG. 1b is another view of the gas turbine system according to FIG. 1a. 1 is a diagram of a first embodiment of an exhaust system according to the present invention. FIG. 2b is another view of the gas turbine system according to FIG. 2a. It is a figure of 2nd Embodiment of the exhaust system which concerns on this invention. 3b is another view of the gas turbine system according to FIG. It is a figure of 3rd Embodiment of the exhaust system which concerns on this invention. FIG. 4b is another view of the gas turbine system according to FIG. 4a. It is a figure of 4th Embodiment of the exhaust system which concerns on this invention. FIG. 5b is another view of the gas turbine system according to FIG. 5a. It is a figure of 5th Embodiment of the exhaust system which concerns on this invention. FIG. 6b is another view of the gas turbine system according to FIG. 6a. It is a figure of 6th Embodiment of the exhaust system which concerns on this invention. FIG. 7b is another view of the gas turbine system according to FIG. 7a. It is a figure of 7th Embodiment of the exhaust system which concerns on this invention. FIG. 8b is another view of the gas turbine system according to FIG. 8a. It is a figure of 8th Embodiment of the exhaust system which concerns on this invention. Fig. 9b is another view of the gas turbine system according to Fig. 9a. It is a figure of 9th Embodiment of the exhaust system which concerns on this invention.

FIG. 1 a is a diagram of a conventional gas turbine system 100 having a catalyst contained in a platform 101 in its exhaust duct 102 oriented orthogonal to the exhaust gas flow 103. As shown in FIG. 1a, the air exiting the turbine system 100 at a high temperature and high speed may be mixed with cooling air in which exhaust gas is supplied by a fan 106 and / or NH ₃ and a hot flue introduced by a blower 109. NH ₃ 107 and hot flue gas 108 pass through an evaporator / mixer 111 as needed, entering the exhaust duct 102 via a transition stage 104, which may have a mixture of gases 108. Exhaust gas, which may include NH ₃ 107 and hot flue gas, is then energized to pass through the catalyst 101. The catalyst required by environmental laws may be for the removal of NO _x. As shown, the catalyst is conventionally arranged as a wall that is orthogonal (perpendicular) to the gas flow 103 through the exhaust duct 102. In the conventional design shown here, the exhaust gas stream 103 is accelerated rapidly and passes through the catalyst wall, resulting in a significant undesired pressure drop and loss of gas turbine efficiency. Stream 103 can pass through an additional catalyst, such as CO catalyst 112, if desired. FIGS. 1 a and 1 b show another view of the gas turbine system 100.

  FIG. 2a is a diagram of a first embodiment of a gas turbine system 200 having an exhaust system according to the present invention. In the first embodiment, the wall-shaped catalyst structure of FIG. 1 a is replaced by a substantially V-shaped catalyst 201. The V-shaped catalyst 201 can be oriented so that the tip of the V faces the direction of the exhaust gas flow 203. The V-shaped catalyst 201 is arranged such that the arms of the V-shaped catalyst are located at substantially the same position or different positions on the exhaust duct as the conventional catalyst, and the V-shape projects outwardly therefrom. ing. The V-shape can be substantially wedge-shaped and includes two structures that may be the same or different lengths.

In this new system, the improved catalyst compared to the conventional design provides an additional cross-sectional area through which the exhaust passes. The catalyst 201 itself, contaminants, in particular a honeycomb design having a series of holes for removing NO _x. The exhaust stream 203 contacts the catalyst 201 at an angle other than 90 degrees to reach a new catalyst configuration, thereby reducing energy loss and thus reducing pressure loss to the system. The cooling stream 206 can be mixed with the flue gas 203 to reduce the temperature of the 203 so that the catalyst 201 can have an improved function at the reduced temperature. The mixed flue gas 203 and the cooling air 206 flow through the catalyst 201 at an angle relative to the flow direction. This process provides additional residence time and cross-sectional area to the system and allows the catalytic reaction of ammonia and NOx. On the other hand, in conventional systems, the small cross-sectional area and the reduced / reduced residence time result in a large drop in pressure and a corresponding great drop in gas turbine efficiency. 2a and 2b are diagrams of a gas turbine system 200. FIG. Stream 203 may optionally pass through an additional catalyst, such as CO catalyst 212, which may be a conventional design arranged according to any of the non-limiting embodiments described herein. it can.

  FIG. 3a shows a second embodiment according to the invention. In this embodiment, the V shape of FIG. 2 a is replaced by a conical catalyst 301 oriented to face the direction of the exhaust gas flow 303. Instead of the generally flat portion with the V-shape of the embodiment of FIG. 2a, FIG. 3a shows a conical shape disposed in the exhaust duct 302 that performs the same function as the V-shaped catalyst of FIG. 2a. . The cone is around the edge of the exhaust duct and narrows in the direction of the exhaust gas flow 303. In an alternative embodiment, the catalyst can be configured as a hollow cone structure. The shape around the catalyst structure is determined by the shape of the corresponding exhaust duct 302. The cone can be oriented so that its central axis is aligned with the exhaust gas flow 303. Alternatively, the cone can be oriented with a central axis oriented at an angle greater than zero with respect to the flow direction of the exhaust gas. The circular (or rectangular) edges that define one end of the cone may be concentrically placed within the section where the cone is placed, or to the exhaust section and the gas flow therethrough. It may be offset or angled. FIGS. 3 a and 3 b are diagrams of a gas turbine system 300. Stream 303 may optionally pass through an additional catalyst, such as a CO catalyst 312, which may be a conventional design arranged according to any of the non-limiting embodiments described herein. it can.

  FIG. 4a shows a third embodiment according to the invention. In this embodiment, a conventional flat wall oriented perpendicular to the exhaust gas flow is replaced by an angled catalyst wall 401. The catalyst is fixed to the exhaust duct and extends rearward toward the exhaust stack, where its further downstream end also substantially contacts the exhaust duct and passes through the catalyst structure 401 before exiting the system. It is configured to require gas. Angled wall embodiments can be placed in the outlet tube instead of or in addition to the exhaust duct 402. FIGS. 4 a and 4 b are diagrams of a gas turbine system 400. Stream 403 may pass through an additional catalyst, such as a CO catalyst 412, which may be of conventional design, arranged according to any of the non-limiting embodiments described herein, if desired. it can.

  FIG. 5a shows a fourth embodiment according to the present invention. In this embodiment, the angled catalyst has been modified to configure as a substantially step-shaped configuration 501. Such an embodiment can be oriented such that the staircase shape is composed of segments that are orthogonal to the exhaust gas flow 503 and other segments that are parallel to the exhaust gas flow 503. In another configuration, the stepped catalyst 501 is comprised of segments that are neither perpendicular nor parallel to the direction of the exhaust gas flow 503. The segments may all be the same length, or the segments may vary in length. The segments may all be oriented at the same angle pair with respect to each other, or the segments may be oriented at various angles. The specific angle selected depends on the particular exhaust duct 502 structure utilized. FIGS. 5 a and 5 b are diagrams of a gas turbine system 500. Stream 503 may pass through an additional catalyst, such as a CO catalyst 512, which may be a conventional design, arranged according to any of the non-limiting embodiments described herein, if desired. it can.

  FIG. 6a is a diagram showing a fifth embodiment according to the present invention. FIG. 6a reverses the V shape of FIG. 2a. In this embodiment, the catalyst wedge 601 faces away from the exhaust gas flow 603. In this configuration, the exhaust gas is divided outward and energized before passing through the catalyst. The V shape here has the advantage of splitting the exhaust stream 603 before passing through the catalyst, unlike the V shape of FIG. 2a which encloses the air flow in the wedge. Both configurations provide an advantage over conventional designs in that additional residence time and surface area are provided in the exhaust stream. FIGS. 6 a and 6 b are diagrams of a gas turbine system 600. Stream 603 may pass through an additional catalyst, such as a CO catalyst 612, which may be of conventional design, arranged according to any of the non-limiting embodiments described herein, if desired. it can.

  FIG. 7a is a diagram showing a sixth embodiment according to the present invention. FIG. 7a reverses the conical shape of FIG. 3a. In this embodiment, the catalyst cone 701 faces away from the exhaust gas flow 703. In this configuration, the exhaust gas is divided outward and energized before passing through the catalyst. The conical shape here has the advantage of splitting the exhaust stream before it passes through the catalyst, unlike the conical shape of FIG. Both configurations provide an advantage over conventional designs in that additional time and surface area are provided to the exhaust stream. FIGS. 7 a and 7 b are diagrams of a gas turbine system 700. Stream 703 may pass through an additional catalyst, such as a CO catalyst 712, which may be of conventional design, arranged according to any of the non-limiting embodiments described herein, if desired. it can.

  FIG. 8a is a diagram showing a seventh embodiment according to the present invention. FIG. 8a is provided with a catalyst 801 having a stepped configuration added to the V shape of FIGS. 2a and 6a. Utilizing the staircase shape shown in FIG. 5a applied to the V-shape of FIGS. 2a and 6a further assists in passing further exhaust gas through the catalyst 801 and reducing the effects of pressure drop. Resulting in additional surface area. FIGS. 8 a and 8 b are diagrams of a gas turbine system 800. Stream 803 may pass through an additional catalyst, such as a CO catalyst 812, which may be a conventional design arranged according to any of the non-limiting embodiments described herein, if desired. it can.

  FIG. 9a is a diagram showing an eighth embodiment according to the present invention. 9a is provided with a catalyst 901 having a stepped configuration added to the conical shape of FIGS. 3a and 7a. Utilizing the stepped shape shown in FIG. 5a applied to the conical shape of FIGS. 3a and 7a further assists in passing further exhaust gas through the catalyst 901 and reducing the effects of pressure drop. Provides additional surface area. FIGS. 9 a and 9 b are diagrams of a gas turbine system 900. Stream 903 may pass through an additional catalyst, such as a CO catalyst 912, which may be a conventional design, arranged according to any of the non-limiting embodiments described herein, if desired. it can.

  FIG. 10 is a diagram showing a ninth embodiment according to the present invention. FIG. 10 shows an alternative configuration of the catalyst 1001 provided in the cylinder 1010 instead of the exhaust duct 1002. Any of the alternative configurations for the catalyst described and shown in connection with FIGS. 2a-9a can be configured and arranged to be installed in the cylinder 1010 or the exhaust duct 1002. Moving the catalyst further downstream, i.e., into the cylinder and through the exhaust duct, provides more time for the gas to cool and slow down without interference. The additional time helps reduce the pressure loss associated with conventional designs.

The delay in the interaction of the flue and / or exhaust gas with the catalyst structure causes the catalyst to pass through the flue and / or exhaust gas at a slower rate, and the catalyst can remove NO _x or other contaminants. The slower speed is achieved using any of a number of catalyst structure designs that are not conventionally available, and the front of the catalyst is intentionally misaligned in the flow direction of the exhaust and / or flue gas. Alternative configurations and arrangements effectively form a cross-sectional area that is large enough for the reduction of contaminants, ie, NO _x .

  The additional surface area functions to better catalyze pollutants in the exhaust gas, thus removing pollutants and at the same time more efficient to significantly reduce the pressure drop associated with conventional systems. Is an effective and effective system. Experiments have found that alternative designs reduce pressure drop by more than 70%. Correspondingly, according to the gas turbine model, the alternative configurations described herein can also lead to an increase in the power output of the associated gas turbine by at least 5 MW (megawatts). In addition, costs were reduced by up to 20% by minimizing the need to increase the size of the exhaust duct.

  For purposes of this application, “flue gas” and “exhaust gas” are used interchangeably to describe a catalyst structure that functions in the exhaust and / or flue gas flow path associated with a gas turbine power plant. This means that the present invention has an advantageous effect.

  Although the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, the invention is not limited to the disclosed embodiments but, conversely, the appended claims. It is to be understood that various modifications and equivalent arrangements included within the spirit and scope of this invention are intended to be covered.

100 gas turbine system 101 platform, catalyst 102 exhaust duct 103 exhaust flow, exhaust gas, flow direction 104 transition stage 106 fan 107 NH ₃
108 Hot flue gas 109 Blower 111 Evaporator / mixer 112 CO catalyst 200 Gas turbine system 201 Catalyst 203 Exhaust flow, flue gas, exhaust gas flow 206 Cooling flow, cooling air 212 CO catalyst 300 Gas turbine system 301 Catalyst 302 Exhaust duct 303 Exhaust gas flow 312 CO catalyst 400 Gas turbine system 401 Catalyst wall, catalyst structure 402 Exhaust duct 403 Flow 412 CO catalyst 500 Gas turbine system 501 Step-shaped catalyst 502 Exhaust duct 503 Flow 512 CO catalyst 600 Gas turbine system 601 Catalyst wedge 603 exhaust stream 612 CO catalyst 700 gas turbine system 701 catalyst cone 703 stream 712 CO catalyst 800 gas turbine system 801 catalyst 803 stream 812 CO catalyst 900 Gaster Bin system 901 Catalyst 903 Flow 912 CO catalyst 1001 Catalyst 1002 Exhaust duct 1010 Tube

Claims (16)

An exhaust duct (102) in fluid communication with exhaust gas (103) from a gas turbine engine (100), wherein the exhaust gas (103) passes through the exhaust duct (102) along a flow direction (103). Exhaust duct (102) flowing through
A catalyst support platform (101) extending to the flow path of the exhaust duct (102) so that the exhaust gas (103) passes through the platform (101), the platform (101) having a catalyst coated surface An exhaust of a gas turbine power plant (100) including an opening, the catalyst support platform (101) including a catalyst support platform (101) having a front surface that is at least partially not perpendicular to the flow direction (103). section.   The exhaust section of a gas turbine power plant (300) according to claim 1, wherein the catalyst support platform (301) has a generally conical shape with a conical axis parallel to the flow direction (303).   The exhaust section of a gas turbine power plant (300) according to claim 2, wherein the conical shape (301) has a V-shaped cross section converging in the flow direction (303).   The exhaust section of a gas turbine power plant (100) according to claim 1, wherein the plurality of openings have an axis oriented in a range of 10 to 90 degrees relative to the flow direction (103).   The exhaust section of a gas turbine power plant (400) according to claim 1, wherein the catalyst support platform (401) is oriented in a plane at an angle to the flow direction (403) in the range of 10 to 90 degrees.   The exhaust section of a gas turbine power plant (500) according to claim 1, wherein the catalyst support platform (501) comprises a stage.   The gas turbine power plant of claim 6, wherein each stage includes a riser pipe in a plane substantially perpendicular to the flow direction (503) and a tread in a plane substantially parallel to the flow direction (503). (500) exhaust section.   The exhaust section of a gas turbine power plant (100) according to claim 1, wherein the catalyst coated surface comprises an oxidizing or reducing agent coating. A transition duct (104);
An exhaust duct (102);
An exhaust outlet tube (110);
A porous catalyst support platform (101) in the exhaust duct (102) or in an exhaust outlet cylinder (110), the catalyst support platform (101) being adapted for exhaust from the gas turbine engine (100) to the platform (101) Extending over the exhaust flow (103) path to flow through, the catalyst support platform (101) has an angle with respect to the direction of the exhaust flow (103) where the exhaust flow (103) is in the range of 10-90 degrees. 101) an exhaust section of a gas turbine power plant (100) arranged to pass through the catalyst coating opening at 101).   The exhaust section of a gas turbine power plant (300) according to claim 9, wherein the catalyst support platform (301) has a generally conical shape with a conical axis parallel to the flow direction (303).   The exhaust section of a gas turbine power plant (200) according to claim 10, wherein the conical shape (201) has a V-shaped cross section converging in the flow direction (203).   The exhaust section of a gas turbine power plant (100) according to claim 9, wherein the plurality of openings have an axis oriented in a range of 10 to 90 degrees relative to the flow direction (103).   The exhaust section of a gas turbine power plant (400) according to claim 9, wherein the catalyst support platform (401) is oriented in a plane at an angle to the flow direction (403) in the range of 10 to 90 degrees.   The exhaust section of a gas turbine power plant (500) according to claim 9, wherein the catalyst support platform (501) comprises a stage.   The gas turbine power plant of claim 14, wherein each stage includes a riser pipe in a plane substantially perpendicular to the flow direction (503) and a tread in a plane substantially parallel to the flow direction (503). (500) exhaust section. The exhaust section of a gas turbine power plant (100) according to claim 9, wherein the catalyst coated surface comprises an oxidizing or reducing agent coating.
System for placing emission reduction catalyst in exhaust duct of gas turbine engine